The uses of rare earth magnets
Rare earth magnets have many applications ranging from Maglev transport systems to Warhammer figurines. Learn more about magnets and the way in which rare earth metals have revolutionised modern technology.
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Background
Names Rare earth magnets are strong and permanent magnets. They are named for the alloys of rare earth elements from which they are made. Despite the name, rare earth elements are in good supply, including the fifteen lanthanoids plus scandium and yttrium. Performance Rare earth magnets have significant performance advantages over regular magnets. Their magnetic field strength is in excess of 1.4 teslas as opposed to the ferrite magnet fields of between 0.5 and 1 tesla. However, they are brittle and susceptible to corrosion, so they are often plated for protection. Magnetisation Like iron, rare earth metals can be magnetised very easily to form a magnet. However, pure rare earth metals only display magnetic properties at very low temperatures. Therefore, they are used to form compound alloys with transition metals. This allows them to maintain their magnetic properties and to form rare earth magnets at higher temperatures. One of the advantages of using rare earth magnets includes their tendency to magnetise only in one direction.
The uses of rare earth magnets
Replace ferrite magnets Due to their stronger magnetic fields, rare earth magnets are increasingly being used to replace conventional ferrite magnets in modern technology. The uses of magnets are diverse, but common applications include computer hard drives and audio speakers. Flashlights and torches Emergency flashlights and torches use these rare earth magnets to function. These products require magnetic fields so as to generate electricity. Linear motors also utilise rare earth magnets as a source of power for inventions such as the Maglev train. Similarly, modern thrill rides and roller coasters also use rare earth magnets for smooth (yet powerful) launch systems. Figure gaming One interesting application for rare earth magnets is in miniature figure gaming. Large brands such as Warhammer, incorporate these powerful magnets into their figures. This allows an easier transition of “ weaponry” between different units. Nuts and screws alternatives Stop Motion Animation has recently begun incorporating these magnets into the process. They provide a practical alternative to traditional nuts and screws. Electric guitar Electric guitar pick-ups utilise rare earth magnets to capture string vibrations and to convert the vibrations into an electric signal. Industries Rare earth magnets are rapidly infiltrating many industries. They provide cheap and effective alternatives to standard ferrite magnets. They can even be purchased from major retailers such as Amazon and eBay, for domestic use.